How many of you have installed a cold air intake on your vehicle?

I was reading on other forums that they are one of the biggest let downs as far as a bolt on items goes on the newwer vehicle.

I have installed them on almost all of the trucks I have purchased and I have noticed a gain in fuel economy.

What is your view on this?

It's not worth the drop in water fording capabilities to me. New Wranglers are actually fairly prone to hydrolocking, CAI just skyrockets that chance. Also, to me a filter like a K&N would not perform as well on filtering when traveling behind another vehicle kicking up VERY fine dust. So give/take on protection and mileage/power.

I would consider one, however I'd just prefer a smooth tube from the box to the intake rather than the entire open filter setup.

I had a 70 Barracuda and had already moved the battery to the trunk so I had lots of room for duct line to rad support. I bought on of the fiberglass dual inlet jobs that encircle a 14 inch standard aftermarket air cleaner. Routed the 4 inch ducts to holes i cut in rad support on each side of the radiator.
The car was .25 seconds faster (low 13's) with NO other changes.
When done right they work.
The problem with the units for newer cars is that most newer cars already have a system that draws cold air.

It depends on how bad the factory air box is restricted, on my 5.7 Ram I saw more of a gain by running a 4" pvc pipe from the TB to the factory airbox than when I had the whole K&N setup with a cone filter.

Back to back testing at the 1/4 I picked up .12-.13 and 1mph in the 1/4 with the PVC pipe and .08 with the K&N intake.

My wifes 5.7 Charger saw little to no gain with a CAI also but the factory air box is designed, the well the inlet and outlet are 5-6" and it has a nice radiused lid.

My neighbor has a 06-07 5.4 F150 and picked up almost 3/10 with the K&N but the factory air box has a bunch of baffles and a small filter, it choked down to 2" or so before the filter.

What I have read is where guys are taking the stock air box on a dodge diesel and mounting a flange connector to the bottom and a 4 inch piece of pvc tubing down in front of the wheel well in the engine bay. They are claiming to get more out of that than a cold air kit.

If you can gain any sort of ram-air effect it will be beneficial. My .25 second improvement was probably as much due to ram as cold.

For every 10 degrees that you reduce the air temp, you pick up a 1% increase in HP. I picked up 3 MPH and .25 with a scoop. I don't think you can expect the same without the ram efect, but you will gain HP unless your vehicle is already getting cool air.

A vast amount of money would be put to better use,
if most vehicles had a gauge like this:

http://www.drillspot.com/products/672321/baldwin_filters_afg30_air_filter_restriction_gauge

The Japanese have a saying that originally came from the American Engineer Edward Deming:

"What gets measured gets improved"

There was a unique generation of Americans who were taught how to look at
MAP (manifold absolute pressure) and
IAT (intake air temperature)
and then use these two numbers to calculate the maximum horsepower a gasoline engine could make during an aircraft take off.
For them, this was quite literally a life or death situation.

That generation is now in their 80s and 90s and slowing dying off.

That generation was not fooled by 'Cold Air Intakes' that only made more noise.

One member of that generation,
Claude Travis
pointed out that if you want to really know if a cold air intake improves MPG at part throttle driving:
take two nearly identical vehicles
put the modification on one of them,
go for a "convoy" style MPG test run,
then swap the mod onto the other vehicle
and repeat the MPG test run a second time.

All cold air intakes
(unless you count turbochargers)
fail the above style test.

During the hot and humid MI summer days I wonder where this "Cold Air" is supposed to come from. K&N really makes EVERY OEM filter and intake system out to be crap when in reality most are very well designed and high quality. I get a kick out of the Dodge Ram and Dakota guys who plop down $300 plus for a cold air system just to find their 360 magnum still gets 13 mpg. I lost respect for K&N years ago.

http://www.dieselpowermag.com/tech/general/0610dp_aftermarket_air_filters/index.html

Notice they are comparing new filters to new filters
(apples to apples)
and don't play the typical magazine trick
of getting an original equipment air filter really dirty on purpose,
then comparing it to a new aftermarket filter.
If you are willing to play that deceptive trick
it is easy to show nearly any hp gain the author wants.

That's a good article. The only thing I'd add is to say (again) that testing on a modified motor at 400hp or so didn't make any difference either.

Dave